Electrothermoconvection in a Dielectric Navier-Stokes-Voigt Viscoelastic Fluid in Sparsely Distributed Porous Medium

In the present paper, the simultaneous effect of a vertical AC electric field, rotation, and internal heat source on the dielectric viscoelastic fluid (Navier-Stokes-Voigt model) saturating a porous medium has been investigated using the Darcy-Brinkman model when heated from below or above. A linear stability analysis employing the normal mode technique is conducted, and the eigenvalue problem is solved exactly for free boundaries. The impact of the electric field, rotation, and internal heat source on the fluid system for stationary convection and oscillatory convection is analyzed numerically and predicted graphically. It has been shown that an increase in the ratio of viscosities, the Taylor number and inverse Darcy number, enforces the stability of the Navier-Stokes-Voigt viscoelastic rotating dielectric fluid layer. However, electrical Rayleigh number has a destabilizing effect on the onset of both stationary and oscillatory convections. Moreover, the Navier–Stokes–Voigt parameter tends to destabilize the onset of oscillatory convection, while it does not affect the onset of stationary convection. It is also predicted that the system is more stable when heated from above than heated from below. Further, the results derived herein also validate the existing results. The results derived herein have not been reported yet in the literature, to the best of the authors' knowledge.